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<meta name="description" content="单例模式  单例模式（Singleton Pattern）是 Java 中最简单的设计模式之一。这种类型的设计模式属于创建型模式，它提供了一种创建对象的最佳方式。 这种模式涉及到一个单一的类，该类负责创建自己的对象，同时确保只有单个对象被创建。这个类提供了一种访问其唯一的对象的方式，可以直接访问，不需要实例化该类的对象。 注意：  1、单例类只能有一个实例。 2、单例类必须自己创建自己的唯一实例。 3、单例类必须给所有其他对象提供这一实..">
		
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			<h1>单例模式</h1>

<p>单例模式（Singleton Pattern）是 Java 中最简单的设计模式之一。这种类型的设计模式属于创建型模式，它提供了一种创建对象的最佳方式。</p>
<p>这种模式涉及到一个单一的类，该类负责创建自己的对象，同时确保只有单个对象被创建。这个类提供了一种访问其唯一的对象的方式，可以直接访问，不需要实例化该类的对象。</p>
<p><b>注意：</b>
</p><ul>
<li>1、单例类只能有一个实例。</li>
<li>2、单例类必须自己创建自己的唯一实例。</li>
<li>3、单例类必须给所有其他对象提供这一实例。</li>
</ul>
<p></p>

<h2 class="tutheader">介绍</h2>
<p><b>意图：</b>保证一个类仅有一个实例，并提供一个访问它的全局访问点。</p>
<p><b>主要解决：</b>一个全局使用的类频繁地创建与销毁。</p>
<p><b>何时使用：</b>当您想控制实例数目，节省系统资源的时候。</p>
<p><b>如何解决：</b>判断系统是否已经有这个单例，如果有则返回，如果没有则创建。</p>
<p><b>关键代码：</b>构造函数是私有的。</p>
<p><b>应用实例：</b>
1、一个党只能有一个主席。
2、Windows 是多进程多线程的，在操作一个文件的时候，就不可避免地出现多个进程或线程同时操作一个文件的现象，所以所有文件的处理必须通过唯一的实例来进行。
3、一些设备管理器常常设计为单例模式，比如一个电脑有两台打印机，在输出的时候就要处理不能两台打印机打印同一个文件。
</p>
<p><b>优点：</b>
1、在内存里只有一个实例，减少了内存的开销，尤其是频繁的创建和销毁实例（比如管理学院首页页面缓存）。
2、避免对资源的多重占用（比如写文件操作）。
</p>
<p><b>缺点：</b>没有接口，不能继承，与单一职责原则冲突，一个类应该只关心内部逻辑，而不关心外面怎么样来实例化。</p>
<p><b>使用场景：</b>
1、要求生产唯一序列号。 
2、WEB 中的计数器，不用每次刷新都在数据库里加一次，用单例先缓存起来。
3、创建的一个对象需要消耗的资源过多，比如 I/O 与数据库的连接等。
</p>
<p><b>注意事项：</b>getInstance() 方法中需要使用同步锁 synchronized (Singleton.class) 防止多线程同时进入造成 instance 被多次实例化。</p>

<h2 class="tutheader">实现</h2>
<p>我们将创建一个 <i>SingleObject</i> 类。<i>SingleObject</i> 类有它的私有构造函数和本身的一个静态实例。 </p>
<p><i>SingleObject</i> 类提供了一个静态方法，供外界获取它的静态实例。<i>SingletonPatternDemo</i>，我们的演示类使用 <i>SingleObject</i> 类来获取 <i>SingleObject</i> 对象。</p>
<img src="./单例模式 _ 菜鸟教程_files/singleton_pattern_uml_diagram.jpg" alt="单例模式的 UML 图">
<h3>步骤 1</h3> 
<p>创建一个 Singleton 类。</p>
<p><i>SingleObject.java</i></p>
<pre class="prettyprint prettyprinted" style=""><span class="kwd">public</span><span class="pln"> </span><span class="kwd">class</span><span class="pln"> </span><span class="typ">SingleObject</span><span class="pln"> </span><span class="pun">{</span><span class="pln">

   </span><span class="com">//创建 SingleObject 的一个对象</span><span class="pln">
   </span><span class="kwd">private</span><span class="pln"> </span><span class="kwd">static</span><span class="pln"> </span><span class="typ">SingleObject</span><span class="pln"> instance </span><span class="pun">=</span><span class="pln"> </span><span class="kwd">new</span><span class="pln"> </span><span class="typ">SingleObject</span><span class="pun">();</span><span class="pln">

   </span><span class="com">//让构造函数为 private，这样该类就不会被实例化</span><span class="pln">
   </span><span class="kwd">private</span><span class="pln"> </span><span class="typ">SingleObject</span><span class="pun">(){}</span><span class="pln">

   </span><span class="com">//获取唯一可用的对象</span><span class="pln">
   </span><span class="kwd">public</span><span class="pln"> </span><span class="kwd">static</span><span class="pln"> </span><span class="typ">SingleObject</span><span class="pln"> getInstance</span><span class="pun">(){</span><span class="pln">
      </span><span class="kwd">return</span><span class="pln"> instance</span><span class="pun">;</span><span class="pln">
   </span><span class="pun">}</span><span class="pln">

   </span><span class="kwd">public</span><span class="pln"> </span><span class="kwd">void</span><span class="pln"> showMessage</span><span class="pun">(){</span><span class="pln">
      </span><span class="typ">System</span><span class="pun">.</span><span class="kwd">out</span><span class="pun">.</span><span class="pln">println</span><span class="pun">(</span><span class="str">"Hello World!"</span><span class="pun">);</span><span class="pln">
   </span><span class="pun">}</span><span class="pln">
</span><span class="pun">}</span></pre>
<h3>步骤 2</h3>
<p>从 singleton 类获取唯一的对象。</p>
<p><i>SingletonPatternDemo.java</i></p>
<pre class="prettyprint prettyprinted" style=""><span class="kwd">public</span><span class="pln"> </span><span class="kwd">class</span><span class="pln"> </span><span class="typ">SingletonPatternDemo</span><span class="pln"> </span><span class="pun">{</span><span class="pln">
   </span><span class="kwd">public</span><span class="pln"> </span><span class="kwd">static</span><span class="pln"> </span><span class="kwd">void</span><span class="pln"> main</span><span class="pun">(</span><span class="typ">String</span><span class="pun">[]</span><span class="pln"> args</span><span class="pun">)</span><span class="pln"> </span><span class="pun">{</span><span class="pln">

      </span><span class="com">//不合法的构造函数</span><span class="pln">
      </span><span class="com">//编译时错误：构造函数 SingleObject() 是不可见的</span><span class="pln">
      </span><span class="com">//SingleObject object = new SingleObject();</span><span class="pln">

      </span><span class="com">//获取唯一可用的对象</span><span class="pln">
      </span><span class="typ">SingleObject</span><span class="pln"> </span><span class="kwd">object</span><span class="pln"> </span><span class="pun">=</span><span class="pln"> </span><span class="typ">SingleObject</span><span class="pun">.</span><span class="pln">getInstance</span><span class="pun">();</span><span class="pln">

      </span><span class="com">//显示消息</span><span class="pln">
      </span><span class="kwd">object</span><span class="pun">.</span><span class="pln">showMessage</span><span class="pun">();</span><span class="pln">
   </span><span class="pun">}</span><span class="pln">
</span><span class="pun">}</span></pre>
<h3>步骤 3</h3>
<p>验证输出。</p>
<pre class="result prettyprint prettyprinted" style=""><span class="typ">Hello</span><span class="pln"> </span><span class="typ">World</span><span class="pun">!</span></pre>

<h2 class="tutheader">单例模式的几种实现方式</h2>
<p>单例模式的实现有多种方式，如下所示：</p>
<h3>1、懒汉式，线程不安全</h3>
<p><b>是否 Lazy 初始化：</b>是</p>
<p><b>是否多线程安全：</b>否</p>
<p><b>实现难度：</b>易</p>
<p><b>描述：</b>这种方式是最基本的实现方式，这种实现最大的问题就是不支持多线程。因为没有加锁 synchronized，所以严格意义上它并不算单例模式。<br>
这种方式 lazy loading 很明显，不要求线程安全，在多线程不能正常工作。</p>
<p><b>代码实例：</b>
</p><pre style="white-space: pre-wrap;" class="prettyprint prettyprinted"><span class="kwd">public</span><span class="pln"> </span><span class="kwd">class</span><span class="pln"> </span><span class="typ">Singleton</span><span class="pln"> </span><span class="pun">{</span><span class="pln">  
    </span><span class="kwd">private</span><span class="pln"> </span><span class="kwd">static</span><span class="pln"> </span><span class="typ">Singleton</span><span class="pln"> instance</span><span class="pun">;</span><span class="pln">  
    </span><span class="kwd">private</span><span class="pln"> </span><span class="typ">Singleton</span><span class="pln"> </span><span class="pun">(){}</span><span class="pln">  
  
    </span><span class="kwd">public</span><span class="pln"> </span><span class="kwd">static</span><span class="pln"> </span><span class="typ">Singleton</span><span class="pln"> getInstance</span><span class="pun">()</span><span class="pln"> </span><span class="pun">{</span><span class="pln">  
    </span><span class="kwd">if</span><span class="pln"> </span><span class="pun">(</span><span class="pln">instance </span><span class="pun">==</span><span class="pln"> </span><span class="kwd">null</span><span class="pun">)</span><span class="pln"> </span><span class="pun">{</span><span class="pln">  
        instance </span><span class="pun">=</span><span class="pln"> </span><span class="kwd">new</span><span class="pln"> </span><span class="typ">Singleton</span><span class="pun">();</span><span class="pln">  
    </span><span class="pun">}</span><span class="pln">  
    </span><span class="kwd">return</span><span class="pln"> instance</span><span class="pun">;</span><span class="pln">  
    </span><span class="pun">}</span><span class="pln">  
</span><span class="pun">}</span><span class="pln">  </span></pre>
<p></p>

<p><b>接下来介绍的几种实现方式都支持多线程，但是在性能上有所差异。</b></p>
<h3>2、懒汉式，线程安全</h3>
<p><b>是否 Lazy 初始化：</b>是</p>
<p><b>是否多线程安全：</b>是</p>
<p><b>实现难度：</b>易</p>
<p><b>描述：</b>这种方式具备很好的 lazy loading，能够在多线程中很好的工作，但是，效率很低，99% 情况下不需要同步。<br>
优点：第一次调用才初始化，避免内存浪费。<br>
缺点：必须加锁 synchronized 才能保证单例，但加锁会影响效率。<br>
getInstance() 的性能对应用程序不是很关键（该方法使用不太频繁）。</p>
<p><b>代码实例：</b>
</p><pre style="white-space: pre-wrap;" class="prettyprint prettyprinted"><span class="kwd">public</span><span class="pln"> </span><span class="kwd">class</span><span class="pln"> </span><span class="typ">Singleton</span><span class="pln"> </span><span class="pun">{</span><span class="pln">  
    </span><span class="kwd">private</span><span class="pln"> </span><span class="kwd">static</span><span class="pln"> </span><span class="typ">Singleton</span><span class="pln"> instance</span><span class="pun">;</span><span class="pln">  
    </span><span class="kwd">private</span><span class="pln"> </span><span class="typ">Singleton</span><span class="pln"> </span><span class="pun">(){}</span><span class="pln">  
    </span><span class="kwd">public</span><span class="pln"> </span><span class="kwd">static</span><span class="pln"> </span><span class="kwd">synchronized</span><span class="pln"> </span><span class="typ">Singleton</span><span class="pln"> getInstance</span><span class="pun">()</span><span class="pln"> </span><span class="pun">{</span><span class="pln">  
    </span><span class="kwd">if</span><span class="pln"> </span><span class="pun">(</span><span class="pln">instance </span><span class="pun">==</span><span class="pln"> </span><span class="kwd">null</span><span class="pun">)</span><span class="pln"> </span><span class="pun">{</span><span class="pln">  
        instance </span><span class="pun">=</span><span class="pln"> </span><span class="kwd">new</span><span class="pln"> </span><span class="typ">Singleton</span><span class="pun">();</span><span class="pln">  
    </span><span class="pun">}</span><span class="pln">  
    </span><span class="kwd">return</span><span class="pln"> instance</span><span class="pun">;</span><span class="pln">  
    </span><span class="pun">}</span><span class="pln">  
</span><span class="pun">}</span><span class="pln"> </span></pre>
<p></p>

<h3>3、饿汉式</h3>
<p><b>是否 Lazy 初始化：</b>否</p>
<p><b>是否多线程安全：</b>是</p>
<p><b>实现难度：</b>易</p>
<p><b>描述：</b>这种方式比较常用，但容易产生垃圾对象。<br>
优点：没有加锁，执行效率会提高。<br>
缺点：类加载时就初始化，浪费内存。<br>
它基于 classloder 机制避免了多线程的同步问题，不过，instance 在类装载时就实例化，虽然导致类装载的原因有很多种，在单例模式中大多数都是调用 getInstance 方法， 但是也不能确定有其他的方式（或者其他的静态方法）导致类装载，这时候初始化 instance 显然没有达到 lazy loading 的效果。</p>
<p><b>代码实例：</b>
</p><pre style="white-space: pre-wrap;" class="prettyprint prettyprinted"><span class="kwd">public</span><span class="pln"> </span><span class="kwd">class</span><span class="pln"> </span><span class="typ">Singleton</span><span class="pln"> </span><span class="pun">{</span><span class="pln">  
    </span><span class="kwd">private</span><span class="pln"> </span><span class="kwd">static</span><span class="pln"> </span><span class="typ">Singleton</span><span class="pln"> instance </span><span class="pun">=</span><span class="pln"> </span><span class="kwd">new</span><span class="pln"> </span><span class="typ">Singleton</span><span class="pun">();</span><span class="pln">  
    </span><span class="kwd">private</span><span class="pln"> </span><span class="typ">Singleton</span><span class="pln"> </span><span class="pun">(){}</span><span class="pln">  
    </span><span class="kwd">public</span><span class="pln"> </span><span class="kwd">static</span><span class="pln"> </span><span class="typ">Singleton</span><span class="pln"> getInstance</span><span class="pun">()</span><span class="pln"> </span><span class="pun">{</span><span class="pln">  
    </span><span class="kwd">return</span><span class="pln"> instance</span><span class="pun">;</span><span class="pln">  
    </span><span class="pun">}</span><span class="pln">  
</span><span class="pun">}</span><span class="pln">  </span></pre>
<p></p>

<h3>4、双检锁/双重校验锁（DCL，即 double-checked locking）</h3>
<p><b>JDK 版本：</b>JDK1.5 起</p>
<p><b>是否 Lazy 初始化：</b>是</p>
<p><b>是否多线程安全：</b>是</p>
<p><b>实现难度：</b>较复杂</p>
<p><b>描述：</b>这种方式采用双锁机制，安全且在多线程情况下能保持高性能。<br>
getInstance() 的性能对应用程序很关键。</p>
<p><b>代码实例：</b>
</p><pre style="white-space: pre-wrap;" class="prettyprint prettyprinted"><span class="kwd">public</span><span class="pln"> </span><span class="kwd">class</span><span class="pln"> </span><span class="typ">Singleton</span><span class="pln"> </span><span class="pun">{</span><span class="pln">  
    </span><span class="kwd">private</span><span class="pln"> </span><span class="kwd">volatile</span><span class="pln"> </span><span class="kwd">static</span><span class="pln"> </span><span class="typ">Singleton</span><span class="pln"> singleton</span><span class="pun">;</span><span class="pln">  
    </span><span class="kwd">private</span><span class="pln"> </span><span class="typ">Singleton</span><span class="pln"> </span><span class="pun">(){}</span><span class="pln">  
    </span><span class="kwd">public</span><span class="pln"> </span><span class="kwd">static</span><span class="pln"> </span><span class="typ">Singleton</span><span class="pln"> getSingleton</span><span class="pun">()</span><span class="pln"> </span><span class="pun">{</span><span class="pln">  
    </span><span class="kwd">if</span><span class="pln"> </span><span class="pun">(</span><span class="pln">singleton </span><span class="pun">==</span><span class="pln"> </span><span class="kwd">null</span><span class="pun">)</span><span class="pln"> </span><span class="pun">{</span><span class="pln">  
        </span><span class="kwd">synchronized</span><span class="pln"> </span><span class="pun">(</span><span class="typ">Singleton</span><span class="pun">.</span><span class="kwd">class</span><span class="pun">)</span><span class="pln"> </span><span class="pun">{</span><span class="pln">  
        </span><span class="kwd">if</span><span class="pln"> </span><span class="pun">(</span><span class="pln">singleton </span><span class="pun">==</span><span class="pln"> </span><span class="kwd">null</span><span class="pun">)</span><span class="pln"> </span><span class="pun">{</span><span class="pln">  
            singleton </span><span class="pun">=</span><span class="pln"> </span><span class="kwd">new</span><span class="pln"> </span><span class="typ">Singleton</span><span class="pun">();</span><span class="pln">  
        </span><span class="pun">}</span><span class="pln">  
        </span><span class="pun">}</span><span class="pln">  
    </span><span class="pun">}</span><span class="pln">  
    </span><span class="kwd">return</span><span class="pln"> singleton</span><span class="pun">;</span><span class="pln">  
    </span><span class="pun">}</span><span class="pln">  
</span><span class="pun">}</span><span class="pln">  </span></pre>
<p></p>

<h3>5、登记式/静态内部类</h3>
<p><b>是否 Lazy 初始化：</b>是</p>
<p><b>是否多线程安全：</b>是</p>
<p><b>实现难度：</b>一般</p>
<p><b>描述：</b>这种方式能达到双检锁方式一样的功效，但实现更简单。对静态域使用延迟初始化，应使用这种方式而不是双检锁方式。这种方式只适用于静态域的情况，双检锁方式可在实例域需要延迟初始化时使用。<br>
这种方式同样利用了 classloder 机制来保证初始化 instance 时只有一个线程，它跟第 3 种方式不同的是：第 3 种方式只要 Singleton 类被装载了，那么 instance 就会被实例化（没有达到 lazy loading 效果），而这种方式是 Singleton 类被装载了，instance 不一定被初始化。因为 SingletonHolder 类没有被主动使用，只有通过显式调用 getInstance 方法时，才会显式装载 SingletonHolder 类，从而实例化 instance。想象一下，如果实例化 instance 很消耗资源，所以想让它延迟加载，另外一方面，又不希望在 Singleton 类加载时就实例化，因为不能确保 Singleton 类还可能在其他的地方被主动使用从而被加载，那么这个时候实例化 instance 显然是不合适的。这个时候，这种方式相比第 3 种方式就显得很合理。</p>
<p><b>代码实例：</b>
</p><pre style="white-space: pre-wrap;" class="prettyprint prettyprinted"><span class="kwd">public</span><span class="pln"> </span><span class="kwd">class</span><span class="pln"> </span><span class="typ">Singleton</span><span class="pln"> </span><span class="pun">{</span><span class="pln">  
    </span><span class="kwd">private</span><span class="pln"> </span><span class="kwd">static</span><span class="pln"> </span><span class="kwd">class</span><span class="pln"> </span><span class="typ">SingletonHolder</span><span class="pln"> </span><span class="pun">{</span><span class="pln">  
    </span><span class="kwd">private</span><span class="pln"> </span><span class="kwd">static</span><span class="pln"> </span><span class="kwd">final</span><span class="pln"> </span><span class="typ">Singleton</span><span class="pln"> INSTANCE </span><span class="pun">=</span><span class="pln"> </span><span class="kwd">new</span><span class="pln"> </span><span class="typ">Singleton</span><span class="pun">();</span><span class="pln">  
    </span><span class="pun">}</span><span class="pln">  
    </span><span class="kwd">private</span><span class="pln"> </span><span class="typ">Singleton</span><span class="pln"> </span><span class="pun">(){}</span><span class="pln">  
    </span><span class="kwd">public</span><span class="pln"> </span><span class="kwd">static</span><span class="pln"> </span><span class="kwd">final</span><span class="pln"> </span><span class="typ">Singleton</span><span class="pln"> getInstance</span><span class="pun">()</span><span class="pln"> </span><span class="pun">{</span><span class="pln">  
    </span><span class="kwd">return</span><span class="pln"> </span><span class="typ">SingletonHolder</span><span class="pun">.</span><span class="pln">INSTANCE</span><span class="pun">;</span><span class="pln">  
    </span><span class="pun">}</span><span class="pln">  
</span><span class="pun">}</span><span class="pln">   </span></pre>
<p></p>

<h3>6、枚举</h3>
<p><b>JDK 版本：</b>JDK1.5 起</p>
<p><b>是否 Lazy 初始化：</b>否</p>
<p><b>是否多线程安全：</b>是</p>
<p><b>实现难度：</b>易</p>
<p><b>描述：</b>这种实现方式还没有被广泛采用，但这是实现单例模式的最佳方法。它更简洁，自动支持序列化机制，绝对防止多次实例化。<br>
这种方式是 Effective Java 作者 Josh Bloch 提倡的方式，它不仅能避免多线程同步问题，而且还自动支持序列化机制，防止反序列化重新创建新的对象，绝对防止多次实例化。不过，由于 JDK1.5 之后才加入 enum 特性，用这种方式写不免让人感觉生疏，在实际工作中，也很少用。<br>
不能通过 reflection attack 来调用私有构造方法。</p>
<p><b>代码实例：</b>
</p><pre style="white-space: pre-wrap;" class="prettyprint prettyprinted"><span class="kwd">public</span><span class="pln"> </span><span class="kwd">enum</span><span class="pln"> </span><span class="typ">Singleton</span><span class="pln"> </span><span class="pun">{</span><span class="pln">  
    INSTANCE</span><span class="pun">;</span><span class="pln">  
    </span><span class="kwd">public</span><span class="pln"> </span><span class="kwd">void</span><span class="pln"> whateverMethod</span><span class="pun">()</span><span class="pln"> </span><span class="pun">{</span><span class="pln">  
    </span><span class="pun">}</span><span class="pln">  
</span><span class="pun">}</span><span class="pln">  </span></pre>
<p></p>

<p><b>经验之谈：</b>一般情况下，不建议使用第 1 种和第 2 种懒汉方式，建议使用第 3 种饿汉方式。只有在要明确实现 lazy loading 效果时，才会使用第 5 种登记方式。如果涉及到反序列化创建对象时，可以尝试使用第 6 种枚举方式。如果有其他特殊的需求，可以考虑使用第 4 种双检锁方式。</p>			
			
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					<div class="comt-tips"><input type="hidden" name="comment_post_ID" value="8906" id="comment_post_ID">
<input type="hidden" name="comment_parent" id="comment_parent" value="0">
</div>
					<button type="submit" name="submit" id="submit" tabindex="5"><i class="fa fa-pencil" aria-hidden="true"></i> 分享笔记</button>
				</div>
			</div>
		
				
					<div class="comt-comterinfo"> 
						<ul id="comment-author-info">
							<li class="form-inline"><label class="hide" for="author">昵称</label><input class="ipt" type="text" name="author" id="author" value="" tabindex="2" placeholder="昵称"><span class="text-muted">昵称 (必填)</span></li>
							<li class="form-inline"><label class="hide" for="email">邮箱</label><input class="ipt" type="text" name="email" id="email" value="" tabindex="3" placeholder="邮箱"><span class="text-muted">邮箱 (必填)</span></li>
							<li class="form-inline"><label class="hide" for="url">引用地址</label><input class="ipt" type="text" name="url" id="url" value="" tabindex="4" placeholder="引用地址"><span class="text-muted">引用地址</span></li>
						</ul>
					</div>
				
			
		</div>

	</form>
	</div>
<script type="text/javascript">
$(function() {
	//初始化编辑器
	
	var editor = new Simditor({
	  textarea: $('#mded'),
	  placeholder: '写笔记...',
	  upload: false,
	  defaultImage: 'http://www.runoob.com/images/logo.png',
	  codeLanguages: '',
	  toolbar: [  'bold','code','ul','ol','image' ]
	});
	editor.on('selectionchanged', function() {
		$(".code-popover").hide();
	});

	// 提交数据
	$("#share_code").click(function() {
		$(".comment-signarea").hide();
		$("#commentform").show();
		
	});

	// 提交笔记
	var commentform=$('#commentform');
	commentform.prepend('<div id="comment-status" ></div>');
	var statusdiv=$('#comment-status');
	
	commentform.submit(function(e){
		e.preventDefault();
		var noteContent = editor.getValue();
		// console.log(noteContent);
		noteContent = noteContent.replace(/<pre><code>/g,"<pre>");
		noteContent = noteContent.replace(/<\/code><\/pre>/g,"</pre>");
		
		// 系列化表单数据
		var comment_parent = 0;
		var is_user_logged_in = $("#is_user_logged_in").val();
		var comment_post_ID =  8906;
		var _wp_unfiltered_html_comment = $("#_wp_unfiltered_html_comment").val();
		var comment = noteContent;
		var author = $("#author").val();
		var url = $("#url").val();
		var email = $("#email").val();
		if(isBlank(author) && is_user_logged_in==0) {
			statusdiv.html('<p  class="ajax-error">请输入昵称！</p>');
		} else if(isBlank(email)  && is_user_logged_in==0) {
			statusdiv.html('<p  class="ajax-error">请输入邮箱！</p>');
		} else {
			// var formdata=commentform.serialize() + "&comment=" + noteContent ;
			// 添加状态信息
			statusdiv.html('<p>Processing...</p>');
			// 获取表单提交地址
			var formurl=commentform.attr('action');
			
			// 异步提交
			$.ajax({
					type: 'post',
					url: formurl,
					dataType:'json',
					data: {"comment_parent":comment_parent,"comment_post_ID":comment_post_ID, "_wp_unfiltered_html_comment":_wp_unfiltered_html_comment,"comment":comment,"url":url, "email":email,"author":author},
					error: function(XMLHttpRequest, textStatus, errorThrown){
					statusdiv.html('<p class="ajax-error" >数据不完整或表单提交太快了！</p>');
				},
				success: function(data, textStatus){
					if(data.errorno=="0") {
						$("#submit").prop('disabled', true);
						statusdiv.html('<p class="ajax-success" >笔记已提交审核，感谢分享笔记！</p>');
						alert('笔记已提交审核，感谢分享笔记！');
					}else{
						statusdiv.html('<p class="ajax-error" >'+data.msg+'</p>');
					}
					commentform.find('textarea[name=comment]').val('');
				}
			});
			setTimeout(function(){
		        $("#submit").prop('disabled', false);
		    }, 10*1000);
		}
		return false;

	});
	
});
function isBlank(str) {
    return (!str || /^\s*$/.test(str));
}
</script>

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function coll() {
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		if(data.error==0) {
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